Proteomics is the study of the subsets of protein present
in different parts of an organism and how they change with
time and varying conditions.

Two-dimensional electrophoresis (2DE)
currently remains the most popular separation technique for
soluble proteins, and allows proteome mapping and
comparison of protein expression under various conditions.
We improved the sensitivity of detection by using
fluorescent dyes. Gel-free proteomics techniques based on
mono- or multidimensional liquid chromatography coupled
with tandem mass spectrometry (MDLC-MSMS) complement our
2DE techniques. Two tandem mass spectrometers, the QSTAR
XL, and the 4800 MALDI-TOF/TOF exist in the
laboratory.

Numerous proteomics approaches were carried out in the
laboratory. One main focus was the comparative analysis of
relative protein expression under different growth
conditions or of different strains of an organism.
Comparative 2DE and stable isotope labelling of peptides
(iTRAQ) followed by MDLC-ESI-MSMS were used for this aim.

"Targeted proteomics” involves
initial protein enrichment by various methodologies.
This approach was widely used for
different projects, especially for protein-protein
interactions and phosphoproteome analyses.
For instance, affinity purifications of
protein complexes using the TAP (Tandem Affinity
Purification) approach resulted in the identification of
partners involved in active protein complexes. Moreover,
quantitative results obtained with SILAC labelling gave
valuable information for the understanding of the protein
order assembly within the pre-60s maturation process
(collaboration with
A Jacquier, Molecular Interaction
Genetics). The TAP method is also
applied to protein analyses of Helicobacter pylori
collaboration
with H de Reuse, Helicobacter
Pathogenesis). After an
enrichment step of phosphorylated proteins, a combination
of 2DE, using specific staining and mass spectrometry
analyses led to the identification of the
Leishmania
donovani
phosphoproteome (collaboration with G
Spaeth, Parasite Virulence).

In parallel to our scientific activity, which involves the
Proteomics platform in many collaborative projects, we are
also dedicated to service activities.